The bull market we're seeing isn't going to last, having already run since the election, investment strategist Joseph Tanious told "Power Lunch."
"I don't think the pace of this rally is sustainable and I think we are going to see some choppiness in the months to come," Tanious, principal of Bessemer Trust, told CNBC.
Tanious admitted that much of the bull market was based on a solid foundation — high profitability, proposed tax cuts, etc. — but that doesn't mean this so-called "Trump rally" is unstoppable. The growth he sees in the S&P 500 right now has to subside.
"[W]hile I agree with a lot of the underlying themes here … I worry just how long in the tooth this business cycle has become, how stretched valuations are," Tanious said.
But not all market watchers are concerned. Paul Hickey, co-founder of the Bespoke Investment Group, says the market will continue to rise. But assuming that all stocks are rising with it would be a mistake, he says.
"Rather than the market that lifts all boats, it's more the Fed-driven market we're seeing and the economically cyclically driven market. …" he said. "We're looking at materials, we're looking at technology, financials."
Importantly, however, he doesn't agree that this bull market is approaching its expiration date. In fact, he thinks pessimistic outlooks like Tanious' are good for the market.
"You need some worry in the market to keep things going, otherwise there's nothing to climb there."